Blend will eventually be usable to ANY BB10 phone running 10.3.x and above. the latest Blend client (updated in December 2014) has actually whitelisted all BB10 phones running the 10.3.x software.

therefore, if you really wanna try Blend, feel free to autoload the leaked 10.3.1.1949 OS to your phone. find it over here, but PLEASE.. READ the thread before you load your OS, as it is LEAKED therefore, be prepared for any bugs/errors.